The thermal efficiency of an engine is

where
W is the work done by the engine
Q is the heat absorbed by the engine to do the work
In this problem, the work done by the engine is W=200 J, while the heat exhausted is Q=600 J, so the efficiency of the machine is
Answer:
A) E = 4.96 x 10³ eV
B) E = 4.19 x 10⁴ eV
C) E = 3.73 x 10⁹ eV
Explanation:
A)
For photon energy is given as:


where,
E = energy of photon = ?
h = 6.625 x 10⁻³⁴ J.s
λ = wavelength = 0.25 nm = 0.25 x 10⁻⁹ m
Therefore,

<u>E = 4.96 x 10³ eV</u>
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B)
The energy of a particle at rest is given as:

where,
E = Energy of electron = ?
m₀ = rest mass of electron = 9.1 x 10⁻³¹ kg
c = speed of light = 3 x 10⁸ m/s
Therefore,


<u>E = 4.19 x 10⁴ eV</u>
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C)
The energy of a particle at rest is given as:

where,
E = Energy of alpha particle = ?
m₀ = rest mass of alpha particle = 6.64 x 10⁻²⁷ kg
c = speed of light = 3 x 10⁸ m/s
Therefore,


<u>E = 3.73 x 10⁹ eV</u>
We know that:
d=vt
d=32mph*5h
d=160mi
Answer:
1963.93 Moles
Explanation:
-We know the standard conversion ratio for the volume of a mole is
Given volume of rooms as 
Convert the volume into liters:
#From our conversion ratio above, we get the volume of air molecules in moles as:

Hence, the volume of air molecules is 1963.93 Moles